FIG. 2.

Detection of the tagged HIV-1 IN. (A and B) Western blot analysis of transfected cells and viral particles with antibody specific for the HIV-1 gag-encoded MA and CA proteins (A) and for the tagging epitope HA (B). Molecular masses (in kilodaltons) are indicated on the left side of panels A and B. Cell lysates containing 30 μg of total proteins and virion preparations containing 50 ng of p24 were analyzed. CTRL, control. (C) High sensitivity of Western blot detection of the HA-tagged IN present in viral particles. The p24 antigen content of viral particles (in nanograms) is indicated.